Hisako Ichiki (一木久子) is a young Japanese girl whose greatest aspiration is one day to be an X-Man. Along with her best friend and fellow student, Wing, Hisako was attacked in the halls of Xavier’s school by the alien villain Ord of Breakworld. Hisako and Wing attempted to oppose Ord, but were overpowered. While both teenagers survived the attack, Wing discovered that he had been injected with Hope, a “cure” for his mutant ability of flight. Despondent, he committed suicide after some goading from a Danger Room hologram of Hisako.

In the wake of this tragedy, Hisako, her teacher Kitty Pryde and other Xavier students found themselves trapped in a sentient and hostile Danger Room with Wing’s reanimated corpse. Danger, as the intelligence began calling itself, eventually left the Institute.

Hisako found classmate Blindfold upset in the restroom. While comforting her, Wolverine, believing he was a defenseless child due to the manipulations of Cassandra Nova, barged into the restroom, followed closely by the feral Beast. Beast began to attack Blindfold, but Hisako used her powers and fought off Beast. Exhausting herself, she fainted. Blindfold and Hisako made their way through the Institute. Blindfold told Hisako she believed someone was awake in the infirmary and they found the unconscious bodies of Colossus and Cyclops. Soon afterward, Shadowcat rose from the floor and asked the girls to explain everything they knew.

Soon after, both Ord and Danger attacked the mansion, where they were confronted by Hisako and then Wolverine where the young girl held her own only to end up slightly impaled by Wolverine claws. Although she only received minor injuries, things didn't get any better when Cassandra Nova chose her to be the evil mutant's new host body. Cassandra was successful in getting Emma Frost to transfer her consciousness into Hisako. S.W.O.R.D then beamed the team, Danger, Ord, and Hisako into a spaceship headed for the Breakworld.

School’s Out / High School Never Ends

The team and Hisako found that S.W.O.R.D. had abducted the X-Men and Hisako because they needed heroes to fight a threat: Breakworld had a weapon capable of destroying the Earth. After flying through space, Ord sent the ship's coordinates to Breakworld's ruler, and he sent a fleet to attack the ship. When the attack was over, the ship was heavily damaged and the X-Men were separated. Hisako ended up with Wolverine. Hisako was given membership to the X-Men and a costume exactly like Shadowcat's. After commenting on how she had a test that week, Wolverine told her that she was an X-Man now and she was there to save the world. She took up the codename Armor, at least until Wolverine could go a day without stabbing her to pick a better one, fulfilling her dream of being an X-Man.

Later, Wolverine and Armor are captured as Emma and the remaining X-Men try to free Cyclops. It is then revealed through a flashback that Leviathan is a fake and that Wolverine and Armor were told to be captured so the X-Men would have men inside Kruun's palace. Kruun only captured and brought Cyclops back to life so as to question him about the fake Leviathan. Cyclops then uses his newly-regained powers to knock out Kruun and free Wolverine and Armor.

Back on earth, Armor attempts to console Wolverine after losing Shadowcat by forcing him to fight/train with her.

When the New X-Men go into the future to fight Victorious, they first see the defeated superhero teams of the time period. One of these teams is the X-Men, led by a future version of Hisako.

Welcome to Paradise / Hotel California

Hisako later accompanies the team to a spaceship graveyard known as Chaparanga where she performs a fastball special with Wolverine and confronts a mysterious man, dubbed Subject X who they find fixing and restarting the eponymous "ghost box" in a spaceship. Subject X is defeated but kills himself rather than surrender information about his intentions and "the Annex."

The X-Men locate Tian, which is an uncharted area of China that no surveillance or satellite system can get through, not even the Chinese government or Cerebro. The X-Men are able to sneak into Tian and discover the headquarters of a group of mutants from another dimension. Sadly, they seem to be dying.

As Armor and Logan go off to search the temple for anyone else, they come across a man who can fire lasers from his fingers. Armor is shocked when the laser goes through her armor and gets shot in the arm. After the X-Men take down their foes, they reveal to the X-Men they have a mutual friend, Forge. After finding Forge on Mt. Wundegore and discovering he has gone mad, he tries to open the Ghost Box. Thanks to the assistance of Abigail Brand and Beast, who borrows Hisako's phone, Brand fires a world-destroying laser at the Ghost Box and the phone, destroying it as well as much of the area while the X-Men escape.

After returning from China, Hisako visits Academy X for a Halloween party with former classmate Meghan. During the party, Cassandra Nova (who had transferred her consciousness into Hisako) takes over Hisako’s body. She activates Vortex’s Weapon X brainwashing to provide a distraction. When Bast tries to stop her, Nova triggers her secondary mutation (shadow teleportation), making her fall into a shadow and disappear. Nova then possesses a student at Academy X that can create matter and has her create a new body for her. In the new body, she takes possession of a Sentinel from the workshop of the school and flies off to find Xavier and kill him. The eXalts are able to stop Nova.

My Generation / Children’s Crusade

Hisako returns to the east coast. The X-Men’s next mission is to go to Africa to assist Mutantes Sans Frontieres, whose base has been overtaken by soldiers. The group was investigating a large number of mutant births in the area. The X-Men quickly take out the troops, and Emma Frost kisses the staff in order to let them download the native language for 48 hours so they can communicate with the locals.

After Beast witnesses the mutations and studies the babies, he discovers they are not mutants and are simply affected by a type of radiation that has spread over the area. Before they can investigate, a cyborg with his own troops that is in charge of the area takes everyone hostage at gun point. Cyclops distracts him while Emma Frost controls all of his troops, and they discover that they must work together in order to find out the cause of the radiation.

In the woods, they find a man running for his life. Wolverine, Beast, and two of the cyborg's best men track him into the jungle. A ghost box opens, and troops known as Furies emerge with guns in order to kill the running man. Wolverine and Beast easily take them down, but the Ghost Box unleashes larger Furies that can morph their arms into weapons and regenerate. Beast is shot down, the cyborg's men are eviscerated, and Wolverine is almost killed. Armor saves Wolverine until he heals.

Emma scans the running man and discovers he is a multiverse teleporter. He escaped from his world, which was overrun by the Furies who had killed every super-powered individual. The Furies were sent after him with the Ghost Box, and now Emma tells Cyclops that during their fight, they must keep one Fury alive or else everyone will die.

A single Fury is left for Emma. She takes control of its mind and performs a "psychic surgery", which alters its programming. Emma changes its orders to say it completed the mission and returned because it had no other commands. Without any reason to pursue further, the outside forces would leave Earth alone.

Emma also reveals to Cyclops that the man they have gives off a giant burst of radiation when he teleports between universes, which is the cause for the babies to mutate. The cyborg kills the teleporter, saying he cannot have a volatile human dirty bomb walking around able to hurt everyone in the area. He says he doesn't like doing these kinds of things, but he has to since it is his job.

Valley of Lost Souls / Empire of the Damned

After a falling-out with Academy X over their decision not to allow Bobby (“Iceman”) to reclaim half of his mutant powers from the artificially created mutant girl, Agape, Hisako helps fight Selene during the Necrosha event. During the battle, Nightcrawler and Iceman face Selene, and Nightcrawler is killed. Many at Xavier’s school blame Academy X staff for Kurt’s death.

Bloodlines

The X-Men team returns to Xavier’s school. Armor and Wolverine are in a Danger Room training session when all of a sudden Armor’s powers flare up. It turns out her mother and brother died, thereby increasing her powers. Armor, Wolverine, Cyclops and Emma all travel to Japan to take Hisako to meet with her father as they plan the funeral arrangements. Wolverine goes solo to hit up a nearby bar. Before he gets to his intended destination the monstrous Fin Fang Foom comes stomping toward him.

Wolverine, Cyclops and Emma Frost head into Tokyo to battle Fin Fang Foom, who is on a rampage. The creature is massive and, as there are only three of them, their work is cut out for them. Elsewhere, Armor and her father attend the funeral for her mother and brother. It’s a solemn occasion and Hisako is very upset. Meanwhile, Director Brewer of Roxxon receives a call from Mentallo, who is wanting to blackmail him for five million dollars – soon upped to eight million when Brewer doesn’t take him seriously. Brewer laughs off the suggestion until he is informed that Tokyo is under attack by Fin Fang Foom, a monster under Mentallo’s control. Mentallo warns Brewer that, if he doesn’t pay, Tokyo won’t be the only refinery he loses. Hisako sees events in Tokyo unfold on television and is told by her father that it’s time for her to stand with her family. The X-Men struggle against the odds and all seems lost until Armor appears, giant-sized and ready to stand with the family she has chosen for herself.

In her gigantic, psionic armored form, Armor helps out her colleagues by taking down Fin Fang Foom all by herself. However, as they watch, the others realize that she is fighting her emotions, as well as the dragon. Still, Armor stops the monster without killing it and appears to remain in control of the situation. Once this crisis has passed, the team heads to Monster Island, only for the Blackbird to be taken down hard by winged creatures. As the jet seems about to crash into a gigantic winged monster, Armor protects the craft with her armored form, the cost of which results in her going into a kind of psychic coma. With Cyclops injured, he stays behind to look after Armor whilst Emma and Wolverine go after Mentallo. The villain receives a call from Roxxon’s Director Brewer, informing him that his bearer bonds have been collected. He then has one of his creatures herd Emma and Logan into a cave where he awaits them with more of his mind-controlled monsters.

Mentallo captures Emma Frost and Wolverine. He explains that this moment and the innovative helmet he’s created is the culmination of his life’s work. He now plans to destroy the island and bury them both under millions of tons of rock. He leaves them to their fate, but he doesn’t get far before Wolverine manages to break free, deactivates the explosives he’s set and confront him. Mentallo tries to take control of the monsters again, but Cyclops appears and destroys the helmet. Not entirely helpless, he tries to use Scott to attack the others, but Emma gets the better of him. He makes his escape, but the creature appears carrying his bearer bonds in a shipping container. It lets go in order to deliver the goods to its master and the container seemingly kills Mentallo as it lands. The X-Men then take Armor back to Japan where her father humbly welcomes her back with open arms. Meanwhile, Roxxon’s Director Brewer is assassinated for being foolish enough to employ Mentallo in the first place.

Powers and Abilities

Psionic Exo-Armor: Hisako can generate colorful psionic body armor that grants her superhuman strength and durability. The body armor is depicted as enveloping her completely and protects her from powerful attacks and greatly strengthens the force behind her offensive blows. In some depictions, her armor grants her enough strength to lift a Skrull ground tank and punch someone through several walls of a building.

Hisako's armor is durable enough to survive the heat caused from a long fall through the atmosphere. Likewise, she is able to fully withstand the impact from falling to the ground from high up in the atmosphere without any injury. She can also cause her armor to release a large amount of solid, concussive energy at once, but it may be difficult to perform. However, her armor is vulnerable to lasers, which are able to pass through it and harm her. This vulnerability is explained when she states later that her armor still has to let light through.

Adamantium is also able to pierce through Hisako's armor, such as Wolverine's claws, although he is not able to go through it with the rest of his body. In this case, she only remained uninjured because the distance between her armor's perimeter and her body was slightly greater than the length of Wolverine's claws. Her armor was also breached by The Fury, however this may be due to the Fury's abilities to counter-act mutant abilities. To some extent, she can shape her armor, such as her ability to form Wolverine-like claws and make them extend outward. In instances of extreme duress, Hisako is also able to expand her armor, greatly increasing its size and shape around her, though her own body remains the same at its center.

Hisako's armor is initially partially explained as being somehow composed of something related to her family lineage and ancestors. It is later described as being composed of memory. This is stated in an issue of Wolverine: Origins, when Hisako's armor is able to withstand blows from the Muramasa blade, which can cut through any material, since memory is "the only material that the blade cannot cut through." Similarly, in Astonishing X-Men, vol. 3 #39, Armor's armor expands and grows to the size of a building due to the fact she feels strongly about not attending her recently deceased mother and brother's wake.

Combat Training: Hisako has also received combat training from Wolverine and classes in tactics from Cyclops.